Prosthesis delivery system with tip travel limiter and method of use

ABSTRACT

A delivery catheter includes a tip, a spindle and a lock mechanism. The tip includes a tapered portion and a tip sleeve. The tip sleeve extends proximally and has a lumen. The spindle includes a plurality of spindle pins. The lock mechanism locks the tip sleeve to the spindle to prevent relative longitudinal movement between the spindle and the tip sleeve. The delivery catheter includes a delivery configuration with the tip sleeve covering the spindle pins and a release configuration with a proximal end of the tip sleeve distal of the spindle pins. The lock mechanism locks the prosthesis delivery system in the release configuration. Each spindle pin of the plurality of spindle pins includes a smooth, curved profile.

FIELD OF THE INVENTION

The present invention relates to systems and methods for intravasculardelivery and deployment of a stent-graft prosthesis. More particularly,the present invention relates to a prosthesis delivery system in whichthe travel of a tip of the prosthesis delivery system is limited.

BACKGROUND OF THE INVENTION

The wall of an aorta is generally elastic and stretches and shrinks toadapt to blood flow. However, with age, and some medical conditions suchas high blood pressure and/or atherosclerosis, the wall of the aorta maybe weakened. Pressure on the weakened section of the aorta mayoverstretch and bulge, forming an aortic aneurysm. Aortic aneurysms mayburst, causing serious bleeding and/or death. While aortic aneurysms mayform in any section of the aorta, they are most common in the abdominalregion. Aneurysms in the abdominal region are known as abdominal aorticaneurysms, or AAA.

The treatment of an aortic aneurysm depends both on the location of theaneurysm and its size. Treatment options may include surgery and/ormedication. Traditional open surgery inflicts significant patienttrauma, requires extensive recovery times and may result inlife-threatening complications. Medication treatment may not besufficient in many cases.

Rather than performing an open surgical endovascular procedure, effortshave been made to perform aneurysm repair using minimally invasivetechniques including percutaneous transcatheter (transluminal) deliveryand deployment, release, or implantation of a stent-graft prosthesis ata treatment site. A stent-graft prosthesis is a stent or stents coupledto a graft material. More particularly, a lumen or vasculature isaccessed percutaneously at a convenient and less traumatic entry point,and the stent-graft prosthesis is routed through the vasculature to thesite where the stent-graft prosthesis is to be deployed. Intraluminaldeployment is typically effected using a delivery catheter with coaxialinner and outer tubes or shafts arranged for relative axial movement.For example, a self-expanding stent-graft prosthesis may be compressedand disposed within a distal end of an outer shaft or sheath componentof the delivery catheter distal of a stop fixed to an inner shaft ormember. The delivery catheter is then maneuvered, typically trackedthrough a body lumen until a distal end of the delivery catheter and thestent-graft prosthesis are positioned at the intended treatment site.The stop on the inner shaft is then held stationary while the outersheath component of the delivery catheter is withdrawn. The stop on theinner shaft prevents the stent-graft prosthesis from being withdrawnwith the outer sheath. As the outer sheath is withdrawn, the stent-graftprosthesis is released from the confines thereof and radiallyself-expands so that at least a portion of it contacts and substantiallyconforms to a portion of the surrounding interior of the lumen, e.g.,the blood vessel wall or anatomical conduit. When fully released, thestent-graft prosthesis extends both distal and proximal of the aneurysmand forms a new passageway within the vasculature, thereby reducingpressure on the weakened wall of the aneurysm.

In recent years, to improve optimal control and alignment duringdeployment and positioning of a stent-graft prosthesis, various tipcapture mechanisms have been incorporated into the delivery systemutilized for percutaneously delivering the stent-graft prosthesis. Tipcapture involves restraining a proximal end stent of the stent-graftprosthesis in conjunction with a main body restraint achieved by otherdelivery system components, such as a tubular outer shaft or sheath. Thetip capture mechanism can be activated at any time during stent-graftprosthesis deployment to suit any number of system characteristicsdriven by the therapy type, stent-graft type, or specific anatomicalconditions that may prescribe the release timing. Typically, the tipcapture release is activated after some or all of the main stent-graftprosthesis body release, and thus provides a means of restraining thestent-graft prosthesis during positioning. Additional restraint of thestent-graft prosthesis is a key characteristic when the operator isattempting to accurately position the stent-graft prosthesis relative toan anatomical target, such as an aneurysm.

For example, U.S. Pat. No. 8,052,732 to Mitchell et al., which is hereinincorporated by reference in its entirety describes tip capturemechanisms that restrain a proximal end stent of the stent-graftprosthesis while the remainder of the stent-graft prosthesis expands,then releases the proximal end stent. The proximal end stent is attachedto the graft material of the stent-graft prosthesis so as to have an“open web” or “free flow” proximal end configuration in which theendmost crowns thereof extend past or beyond the graft material suchthat the endmost crowns are exposed or bare, and thus free to interactwith a tip capture mechanism and couple the prosthesis to the deliverysystem.

However, attendant with the percutaneous delivery and release of astent-graft prosthesis at a treatment location, the distal portion ofthe delivery catheter must be retracted through the deployed stent-graftprosthesis for removal from the patient. With current delivery catheterdesigns, a gap forms between components of the tip capture mechanism ofthe delivery catheter as the stent-graft prosthesis is deployed. Thisgap may comprise multiple edges that may snag, catch, tear, or otherwisedamage the deployed stent-graft prosthesis or anatomy as the distalportion of the delivery catheter is withdrawn through the deployedstent-graft prosthesis.

Accordingly, there is a need for improved delivery catheter designs andmethods that improve the release of the stent-graft prosthesis, improvethe ease with which a distal portion of the delivery catheter may beremoved, and minimize the potential of the delivery catheter to damagethe deployed stent-graft prosthesis or anatomy during the removal of thedistal portion of the delivery catheter.

BRIEF SUMMARY OF THE INVENTION

Embodiments hereof are directed to a delivery catheter including a tip,a spindle, and a lock mechanism. The tip includes a tapered portion anda tip sleeve. The tip sleeve extends proximally and has a lumen. Thespindle includes a plurality of spindle pins. The lock mechanism locksthe tip sleeve to the spindle, thereby preventing relative longitudinalmovement between the tip sleeve and the spindle.

Embodiments hereof are also directed to a prosthesis delivery systemincluding a stent-graft prosthesis and a delivery catheter. Thestent-graft prosthesis includes a proximal bare stent, at least onestent ring distal of the proximal bare stent and a graft material. Thestent-graft prosthesis has a radially compressed configuration fordelivery within a vasculature and a radially expanded configuration fordeployment. The delivery catheter has a delivery configuration and arelease configuration. The delivery catheter includes a tip, a spindle,a lock mechanism, and an outer sheath. The tip includes a taperedportion and a tip sleeve extending proximally. The tip sleeve isconfigured to retain a proximal portion of the stent-graft prosthesis ina radially compressed state for delivery to a treatment location. Thespindle includes a plurality of spindle pins. The lock mechanism isconfigured to lock the tip sleeve to the spindle to prevent relativelongitudinal movement between the spindle and the tip sleeve when thedelivery catheter is in the release configuration. The outer sheath isconfigured to retain a distal portion of the stent-graft prosthesis in aradially compressed state for delivery to a treatment location.

Embodiments hereof are further related to a method of delivering andreleasing a stent-graft prosthesis. The method includes loading astent-graft prosthesis onto a delivery catheter. The delivery catheterincludes an outer sheath, a spindle, an inner shaft, a tip and a lockmechanism. The tip includes tapered portion and a tip sleeve. Thedelivery catheter is positioned at a desired treatment location within avessel. Once positioned at the desired treatment location, the outersheath is retracted and a first portion of the stent-graft prosthesisreturns to an expanded state. With the first portion of the stent-graftprosthesis in the expanded state, the inner shaft of the deliverycatheter is advanced distally and a second portion of the stent-graftprosthesis returns to an expanded state. Further, the inner shaft isadvanced distally to engage the lock mechanism and lock the tip sleeveto the spindle.

BRIEF DESCRIPTION OF DRAWINGS

The foregoing and other features and advantages of the invention will beapparent from the following description of embodiments thereof asillustrated in the accompanying drawings. The accompanying drawings,which are incorporated herein and form a part of the specification,further serve to explain the principles of the invention and to enable aperson skilled in the pertinent art to make and use the invention. Thedrawings are not to scale.

FIG. 1 depicts a side view of a prosthesis delivery system in accordancewith an embodiment hereof.

FIG. 2 depicts a longitudinal cross-sectional view of the prosthesisdelivery system of FIG. 1, wherein a delivery catheter of the prosthesisdelivery system is in a delivery configuration and a stent-graftprosthesis is in a radially compressed configuration.

FIG. 2A depicts a longitudinal cross-sectional view of a distal portionof the prosthesis delivery system of FIG. 1, wherein the deliverycatheter is in a partial release configuration.

FIG. 2B depicts a longitudinal cross-sectional view of the distalportion of the prosthesis delivery system of FIG. 1, wherein thedelivery catheter is in the release configuration.

FIG. 2C depicts a cross-sectional view of the prosthesis delivery systemtaken at line 2C-2C of FIG. 1.

FIG. 3 depicts a perspective view of an exemplary stent-graft prosthesissuitable for use with the prosthesis delivery system of FIG. 1.

FIG. 4 depicts a side view of a spindle of the delivery catheter of FIG.2.

FIG. 5 depicts a side view of a tip of the delivery catheter of FIG. 2.

FIG. 6 depicts a perspective view of a portion of the tip sleeve of FIG.3, wherein a distal portion of the tip sleeve has been removed forimproved visibility of a plurality of tabs.

FIG. 7 depicts a longitudinal cross-sectional view of a lock mechanismof the delivery catheter of FIG. 2 taken along the longitudinalcenterline of the delivery catheter, wherein the delivery catheter is inthe delivery configuration.

FIG. 8 depicts a longitudinal cross-sectional view of the lock mechanismof the delivery catheter of FIG. 2 taken along the longitudinalcenterline of the delivery catheter, wherein the delivery catheter is inthe release configuration.

FIG. 9 depicts a side view of a distal portion of the prosthesisdelivery system of FIG. 1, wherein the delivery catheter is in adelivery configuration and a portion of an outer sheath of the deliverycatheter is transparent for clarity.

FIG. 10 depicts a side view of the distal portion of the prosthesisdelivery system of FIG. 1, wherein the delivery catheter is in a releaseconfiguration and a portion of an outer sheath of the delivery catheteris transparent for clarity.

FIG. 11 depicts a longitudinal cross-sectional view of a prosthesisdelivery system in accordance with another embodiment hereof, wherein adelivery catheter of the prosthesis delivery system is in a deliveryconfiguration and a stent-graft prosthesis is in a radially compressedconfiguration.

FIG. 12 depicts a side view of a spindle of the delivery catheter ofFIG. 11.

FIG. 13 depicts a partial perspective view of a lock mechanism of thedelivery catheter of FIG. 11, wherein a proximal portion of a spindleand a proximal portion of a tip sleeve have been removed for clarity.

FIG. 14 depicts a longitudinal cross-sectional view of a lock mechanismof the delivery catheter of FIG. 11 taken along the longitudinalcenterline of the delivery catheter, wherein the delivery catheter is inthe delivery configuration.

FIG. 15 depicts a longitudinal cross-sectional view of the lockmechanism of the delivery catheter of FIG. 11 taken along thelongitudinal centerline of the delivery catheter, wherein the deliverycatheter is in the release configuration.

FIG. 16 depicts a side view of a distal portion of the prosthesisdelivery system of FIG. 11, wherein the delivery catheter is in adelivery configuration and a portion of an outer sheath of the deliverycatheter is transparent for clarity.

FIG. 17 depicts a side view of the distal portion of the prosthesisdelivery system of FIG. 11, wherein the delivery catheter is in arelease configuration and a portion of an outer sheath of the deliverycatheter is transparent for clarity.

FIG. 18 depicts a sectional cut-away view of a vessel illustrating amethod step of using the prosthesis delivery system of FIG. 1 to deliverand position a stent-graft prosthesis within the vessel in accordancewith an embodiment hereof, wherein the prosthesis delivery system isshown having been advanced to a desired treatment site adjacent ananeurysm.

FIG. 19 is a sectional cut-away view of the vessel illustrating a methodstep of using the prosthesis delivery system of FIG. 1 to deliver andposition a stent-graft prosthesis within the vessel in accordance withan embodiment hereof, wherein an outer sheath of a delivery catheter hasbeen retracted proximally and a first portion of the stent-graftprosthesis has been released to an expanded state.

FIG. 20 is a sectional cut-away view of the vessel illustrating a methodstep of using the prosthesis delivery system of FIG. 1 to deliver andposition a stent-graft prosthesis within the vessel in accordance withan embodiment hereof, wherein an inner shaft of the delivery catheterhas been advanced distally, a tip sleeve and a spindle of the deliverycatheter are locked together, and a second portion of the stent-graftprosthesis has been released to an expanded state.

FIG. 21 is a sectional cut-away view of the vessel illustrating a methodstep of using the prosthesis delivery system of FIG. 1 to deliver andposition a stent-graft prosthesis within the vessel in accordance withan embodiment hereof, wherein delivery catheter has been retractedproximally through the stent-graft prosthesis.

DETAILED DESCRIPTION OF THE INVENTION

Specific embodiments of the present invention are now described withreference to the figures, wherein like reference numbers indicateidentical or functionally similar elements. The terms “distal” and“proximal”, when used in the following description to refer to adelivery system, a delivery catheter, or delivery components are withrespect to a position or direction relative to the treating clinician.Thus, “distal” and “distally” refer to positions distant from or in adirection away from the treating clinician, and the terms “proximal” and“proximally” refer to positions near or in a direction toward thetreating clinician. The terms “distal” and “proximal”, when used in thefollowing description to refer to a native vessel, native valve, or adevice to be implanted into a native vessel or native valve, such as astent-graft prosthesis, are with reference to the direction of bloodflow. Thus, “distal” and “distally” refer to positions in a downstreamdirection with respect to the direction of blood flow and the terms“proximal” and “proximally” refer to positions in an upstream directionwith respect to the direction of blood flow.

The following detailed description is merely exemplary in nature and isnot intended to limit the invention or the application and uses of theinvention. Although the description of embodiments hereof is in thecontext of the treatment of blood vessels such as the aorta, theinvention may also be used in any other body passageways where it isdeemed useful. Furthermore, there is no intention to be bound by anyexpressed or implied theory presented in the preceding technical field,background, brief summary or the following detailed description.

FIGS. 1-10 illustrates a prosthesis delivery system 100 in accordancewith an embodiment hereof. The prosthesis delivery system 100 includes adelivery catheter 102, also referred to herein as a delivery device, anda stent-graft prosthesis 201 mounted in a radially compressedconfiguration at a distal portion 199 of the delivery catheter 102, asshown in FIGS. 1-2. FIG. 1 is a side view of the prosthesis deliverysystem 100, FIG. 2C is cross-section of the prosthesis delivery system100 taken at line 2C-2C of FIG. 1, and FIG. 2 is a sectional view of theprosthesis delivery system 100. The prosthesis delivery system 100 isconfigured to deliver and release or deploy the stent-graft prosthesis201 at a desired treatment location. Accordingly, the prosthesisdelivery system 100 is sized and configured to be advanced through avasculature in a minimally invasive manner. An introducer sheath (notshown) or a guide catheter (not shown) may be used with the deliverycatheter 102 to minimize intravascular trauma during introduction,tracking and delivery of the delivery catheter 102 to the desiredtreatment location.

FIG. 3 shows an exemplary embodiment of the stent-graft prosthesis 201suitable for use with the prosthesis delivery system 100. Thestent-graft prosthesis 201 includes a proximal end 203, a distal end205, and a lumen 207 extending from the proximal end 203 to the distalend 205. The stent-graft prosthesis 201 further includes a proximal bareor anchor stent 209, a distal bare or anchor stent 211, a plurality ofstent rings 213 and a graft material 215. While described herein withthe proximal bare stent 209, the distal bare stent 211, and theplurality of stent rings 213, the stent-graft prosthesis 201 mayalternatively be formed from unitary laser cut tube, or any othersuitable scaffold or stent structure. The stent-graft prosthesis 201includes a radially compressed configuration for delivery and a radiallyexpanded configuration when deployed. When the stent-graft prosthesis201 is in the radially expanded configuration at a desired treatmentlocation, the stent-graft prosthesis 201 is configured to repair ananeurysm within a vessel.

The proximal bare stent 209 is a stent ring configured to anchor theproximal end 203 of the stent-graft prosthesis 201 to the wall of avessel when the stent-graft prosthesis 201 is in the radially expandedconfiguration. The proximal bare stent 209 includes a plurality ofopenings 217 defined by proximal apexes 219 of the proximal bare stent209. As will be explained in more detail herein, each of the pluralityof openings 217 is configured to receive a corresponding spindle pin 120(visible in FIG. 4) of a spindle 108 (visible in FIG. 4) when thestent-graft prosthesis 201 is in the radially compressed configurationand loaded on the delivery catheter 102 (visible in FIG. 1). A distalportion of the proximal bare stent 209 is coupled to a proximal portionof the graft material 215.

Similarly, the distal bare stent 211 is a stent ring configured toanchor the distal end 205 of the stent-graft prosthesis 201 to the wallof the vessel when the stent-graft prosthesis 201 is in the radiallyexpanded configuration. A proximal portion of the distal bare stent 211is coupled to a distal portion of the graft material 215. While thestent-graft prosthesis 201 is described herein with the distal barestent 211, in an alternative embodiment, the distal bare stent 211 maybe omitted from the stent-graft prosthesis 201.

The plurality of stent rings 213 are configured to support the graftmaterial 215 when the stent-graft prosthesis 201 is in the radiallyexpanded configuration. In other words, the plurality of stent rings 213hold the lumen 207 of the stent-graft prosthesis 201 open when thestent-graft prosthesis 201 is in the radially expanded configuration.Each stent ring 213 is coupled to an inner surface of the graft material215, although it will be understood by one of ordinary skill in the artthat stent rings 213 may alternatively be coupled to an outer surface ofthe graft material.

In embodiments hereof, the proximal and distal bare stents 209, 211, andeach of the plurality of support stents 213 is self-expanding to returnto a radially expanded state from a radially compressed state. Theproximal and distal bare stents 209, 211, and each of the plurality ofsupport stents 213 may be formed of various materials including, but notlimited to stainless steel, nickel-titanium alloys (e.g. NITINOL), orother suitable materials. “Self-expanding” as used herein means that astructure has a mechanical memory to return to the radially expandedconfiguration. The proximal and distal bare stents 209, 211, and each ofthe plurality of support stents 213 may be coupled to the graft material215 by method such as, but not limited to sutures, adhesives, or othermethods suitable for the purposes described herein.

As shown in FIG. 3, the graft material 215 is of a generally tubularshape. The graft material 215 has a longitudinal length L, which mayvary based upon the application. The graft material 215 may be formedfrom any suitable graft material, for example and not limited to, alow-porosity woven or knit polyester, DACRON material, expandedpolytetrafluoroethylene, polyurethane, silicone, or other suitablematerials. In another embodiment, the graft material could also be anatural material such as pericardium or another membranous tissue suchas intestinal submucosa.

The stent-graft prosthesis 201 is deployed at the site of an aneurysmsuch that the stent-graft prosthesis 201 spans the aneurysm. Morespecifically, when the stent-graft prosthesis 201 is in the radiallyexpanded configuration at the site of an aneurysm, the proximal barestent 209 is disposed proximal of the aneurysm and anchors the proximalend 203 of the stent-graft prosthesis 201 to healthy tissue proximal ofthe aneurysm. Similarly, the distal bare stent 211 is disposed distal ofthe aneurysm and anchors the distal end 205 of the stent-graftprosthesis 201 to healthy tissue distal of the aneurysm when thestent-graft prosthesis 201 is in the radially expanded configuration atthe site of an aneurysm. The graft material 215 spans the aneurysm andthe lumen 207 provides a conduit for blood flow through the vessel,thereby reducing pressure on the aneurysm.

The stent-graft prosthesis 201 is described and illustrated herein tofacilitate description of the systems, devices and methods to deliverand release a stent-graft prosthesis according to embodiments hereof. Itis understood that the stent-graft prosthesis 201 is merely exemplaryand any number of alternate stent-graft prostheses can be used with thesystems, devices and methods described herein. For example, and not byway of limitation, the number of apexes of the proximal bare stent 209,the distal bare stent 211, and each of the ring stents 213 may begreater or less than shown in FIG. 3. Further, while shown with three(3) stent rings, the stent-graft prosthesis 201 may include more orfewer stent rings 213 as required by the application.

As shown in FIG. 2, the delivery catheter 102 includes a handle 104, anouter sheath 106, a spindle 108, a spindle shaft 110, a tip 112including a tapered distal portion 195 and a tip sleeve 114, an innershaft 116, and a lock mechanism 118. The delivery catheter 102 isconfigured to retain the stent-graft prosthesis 201 in a radiallycompressed configuration for delivery to the desired treatment location.The delivery catheter 102 includes a delivery configuration shown inFIG. 2 in which the tip sleeve 114 covers a plurality of spindle pins120 of the spindle 108 and the outer sheath 106 covers the spindle 108,a partial release configuration shown in FIG. 2A in which the tip sleeve114 covers the plurality of spindle pins 120 and the outer sheath 106has been retracted such that the outer sheath 106 does not cover thespindle 108, and a release configuration shown in FIG. 2B in which tipsleeve 114 has been advanced such that a proximal end of the tip sleeve114 is distal of the plurality of spindle pins 120 and the lockmechanism 118 locks the delivery catheter 102 in the releaseconfiguration.

The handle 104 includes a housing 122, a first actuating mechanism 124and a second actuating mechanism 126, as shown in FIG. 2. The handle 104is configured with the first and the second actuating mechanisms 124,126 each extending through the housing 122 for interfacing by a user.The first actuating mechanism 124 is configured to retract or pull theouter sheath 106 proximally with respect to the spindle shaft 110. Thesecond actuating mechanism 126 is configured to push or advance theinner shaft 116 distally with respect to the spindle shaft 110 such thatthe tip 112, including the tip sleeve 114, move distally relative to thespindle 108. The handle 104 provides a surface for convenient handlingand grasping by a user, and can have a variety of shapes, including, butnot limited to a cylindrical shape. While the handle 104 is shown with aspecific style of first and second actuating mechanisms 124, 126, thisis not meant to limit the design, and various actuating mechanisms maybe utilized such as, but not limited to axially-slidable levers, rotaryrack and pinion gears, or other applicable actuating mechanisms.

As best shown in the cross-sectional view of FIG. 2C, the deliverycatheter 102 includes the outer sheath 106, the spindle shaft 110, andthe inner shaft 116 concentrically disposed about each other. Morespecifically, the spindle shaft 110 is concentrically disposed about theinner shaft 116, and the outer sheath 106 is concentrically disposedabout the spindle shaft 110.

As best shown in FIG. 2, the outer sheath 106 includes a proximal end128, a distal end 130, and a lumen 132. The lumen 132 extends from theproximal end 128 to the distal end 130 of the outer sheath 106 and issized to receive the spindle shaft 110, the spindle 108 and the tipsleeve 114. A distal portion of the outer sheath 106 is configured toretain a first portion 221 of the stent-graft prosthesis 201 in aradially compressed state for delivery to the desired treatmentlocation. The first portion 221 of the stent-graft prosthesis 201, asused herein, means that portion of the stent-graft prosthesis 201disposed over the spindle shaft 110 and the spindle 108 but notencapsulated by the tip sheath 114 when the prosthesis delivery system100 is in the delivery configuration of FIG. 2. A second portion 223 ofthe stent-graft prosthesis 201, as used herein, means that portion ofthe stent-graft prosthesis 201 disposed over the spindle 108 and held ina radially compressed state by the tip sheath 114 when the prosthesisdelivery system 100 is in the delivery configuration of FIG. 2. Theproximal end 128 of the outer sheath 106 is configured for fixedconnection to the handle 104. More particularly, the proximal end 128extends proximally into the housing 122 of the handle 104 and a proximalportion 134 of the outer sheath 106 is rigidly connected to the firstactuating mechanism 124 of the handle 104. The proximal portion 134 iscoupled to the first actuating mechanism 124 such that movement of thefirst actuating mechanism 124 causes the outer sheath 106 to moverelative to the spindle shaft 110, the spindle 108, the inner shaft 116,the tip 112, and the handle 104.

The spindle shaft 110 includes a proximal end 156, a distal end 158, anda lumen 160. The lumen 160 extends from the proximal end 156 to thedistal end 158 of the spindle shaft 110. The lumen 160 is sized toreceive the inner shaft 116 such that the inner shaft 116 islongitudinally slidable relative to the spindle shaft 110 when thedelivery catheter 102 is in the delivery configuration. The distal end158 of the spindle shaft 110 is attached to a proximal end 140 of thespindle 108 such that the lumen 160 of the spindle shaft islongitudinally aligned with the lumen 138 of the spindle 108, forming acontinuous lumen from the proximal end 156 of the spindle shaft 110 tothe distal end 142 of the spindle 108. The proximal end 156 of thespindle shaft 110 is configured for fixed connection to the handle 104.The spindle shaft 110 may be coupled to the spindle 108 for example, andnot by way of limitation by adhesives, welding, clamping, and othercoupling methods.

Referring again to FIG. 2, the inner shaft 116 is a substantially hollowbody including a proximal end 188, a distal end 190 and a lumen 192. Thelumen 192 extends from the proximal end 188 to the distal end 190 and issized to slidably receive auxiliary devices (e.g. a guidewire). Thedistal end 190 of the inner shaft 116 is attached to the proximal end162 of the tapered portion 195 of the tip 112 and the inner shaft 116extends proximally through the spindle 108 and the spindle shaft 110 toat least the second actuating mechanism 126. More precisely, the innershaft 116 extends proximally through the housing 122 of the handle 104and a proximal portion 194 of the inner shaft 116 is rigidly connectedto the second actuating mechanism 126 of the handle 104. The proximalportion 194 is coupled to the second actuating mechanism 126 such thatmovement of the second actuating mechanism 126 causes the inner shaft116, the tip 112, including the tip sleeve 114, to move relative to thespindle shaft 110, the spindle 108, the outer sheath 106 and the handle104. While the inner shaft 116 is described herein as single component,this is not meant to be limiting, and the inner shaft 116 may includecomponents such as, but not limited to a proximal shaft, a distal shaft,or other components. The tip 112 may be coupled to the inner shaft 116,for example, and not by way of limitation by adhesives, welding,clamping, and other coupling devices as appropriate.

The outer shaft 106, the spindle shaft 110, and the inner shaft 116 mayeach be constructed of materials such as, but not limited topolyurethane, polyether block amide (PEBA), polyamide polyether blockcopolymer, polyethylene, or other materials suitable for the purposes ofthe present disclosure. The proximal portion 134 of the outer sheath106, the proximal end 156 of the spindle shaft 110, and the proximalportion 194 of the inner shaft 116 may be coupled to the first actuatingmechanism 124, the handle 104, and the second actuating mechanism 126,respectively, for example, and not by way of limitation by adhesives,welding, clamping, and other coupling devices as appropriate.

As previously described, the spindle 108 is disposed at the distal end158 of the spindle shaft 110. FIG. 4 illustrates a side view of thespindle 108 removed from the prosthesis delivery system 100 forillustrative purposes only. As shown in FIG. 4, the spindle 108 includesa generally tubular body 136, a lumen 138 extending from the proximalend 140 to a distal end 142, a plurality of spindle pins 120, and aradial groove 144 defined by a proximal wall 148 and a distal wall 150.The term “generally” or “substantially” as used herein, particularlywith respect to the terms “cylindrical”, “flat”, and “tubular” meanswithin normal manufacturing tolerances. The spindle 108 is configured tobe slidably disposed within the tip sleeve 114 of the tip 112 such thatthe tip sleeve 114 may move relative to the spindle 108. The lumen 138is configured to slidably receive the inner shaft 116.

The proximal wall 148 of the spindle 108 includes an outer shoulder 154,a crown 147, and an inner shoulder 149. The outer shoulder 154 of theproximal wall 148 includes a smooth, angled or tapered outer surface155. The outer surface 155 is configured to ease the release of thestent-graft prosthesis 201 as the delivery catheter 102 transitions fromthe delivery configuration to the release configuration. More precisely,the outer surface 155 of the proximal wall 154 makes expansion of thestent-graft prosthesis 201 from the radially compressed configuration tothe radially expanded configuration easier as the frictional forcesbetween the expanding stent-graft prosthesis 201 and the outer surface155 of the proximal wall 149 are reduced by the tapered or angledprofile of the outer surface 155. Further, the stent-graft-prosthesis201 will not catch or otherwise hang-up on the outer surface 155 as thestent-graft prosthesis 201 radially expands. The outer surface 155 ofthe outer shoulder 154 is further configured to create a taperedtransition from the spindle 108 to the tip sheath 114 when the deliverycatheter 102 is in the release configuration such that the stent-graftprosthesis 201 may not catch or otherwise snag on the transition betweenthe spindle 108 and the tip sheath 114 as the delivery catheter 102 isproximally retracted through the deployed stent-graft prosthesis 201.The crown 147 of the proximal wall 148 is substantially flat such thatwhen the delivery catheter 102 is in the release configuration, thetransition between the spindle 108 and the tip sheath 114 is minimized.The term “flat” as used herein means that the surface is planar andoriented parallel to a longitudinal axis of the spindle 108. The term“minimized” as used herein means that the distance between the adjacentsurfaces of two components is reduced to the smallest possible amount ordegree. Thus, minimization of the transition between the spindle 108 andthe tip sheath 114 reduces the possibility that the stent-graftprosthesis 201 may catch or otherwise snag on the spindle 108 and/or thetip sheath 114 as the delivery catheter 102 is proximally retractedthrough the deployed stent-graft prosthesis 201. Accordingly, theconfiguration of the spindle 108 eases the removal of the distal portion199 of the delivery catheter 102 from within the stent-graft prosthesis201. The distal wall 150 includes a crown 151 and an inner shoulder 153.Non-limiting examples of materials suitable for the construction of thespindle 108 include polyurethane, polyether block amide (PEBA),polyamide polyether block copolymer, polyethylene, or other materialssuitable for the purposes of the present disclosure.

The plurality of spindle pins 120 are circumferentially spaced aroundthe body 136 of the spindle 108. Each spindle pin 120 extends radiallyoutward from the body 136 of the spindle 108 such that an outer profile146 of each spindle pin 120 is disposed adjacent to an inner surface ofthe tip sleeve 114 when the delivery catheter 102 is in the deliveryconfiguration. The plurality of spindle pins 120 of the spindle 108 areconfigured to maintain the longitudinal position of the stent-graftprosthesis 201 in relation to the spindle 108 of the delivery catheter102 as the delivery catheter 102 transitions from the deliveryconfiguration to the release configuration.

Each spindle pin 120 is a raised bump or protrusion including a smooth,curved outer surface or profile 146. The outer profile 146 is configuredto ease the release of the stent-graft prosthesis 201 from the deliverycatheter 102. More specifically, the outer profile 146 makes expansionof the stent-graft prosthesis 201 from the radially compressedconfiguration to the radially expanded configuration easier as thefrictional forces between the expanding stent-graft prosthesis 201 andthe outer profile 146 of each spindle pin 120 is reduced by the curvedprofile of the outer profile 146. Further, the stent-graft-prosthesis201 will not catch or otherwise hang-up on the outer profile 146 as thestent-graft prosthesis 201 radially expands. The smooth, curved outerprofile 146 is further configured to enable snag-free/catch-free removalof the spindle 108 from the deployed stent-graft prosthesis 201, asdescribed below. While illustrated in FIG. 4 with a specific number ofspindle pins 120, this is not meant to be limiting, and more or fewerspindle pins 120 may be utilized.

The radial groove 144 is defined between the proximal wall 148 and thedistal wall 150 at a distal portion of the spindle 108. As will bedescribed in more detail herein with respect to FIG. 8, the radialgroove 144 is configured to retain a plurality of tabs 152 (visible inFIG. 5) of the tip sleeve 114 (visible in FIG. 5), when the deliverycatheter 102 (visible in FIG. 5) is in the release configuration. Theradial groove 144 is formed with a sufficient depth D1 optimized suchthat each tab 152 (visible in FIG. 4), once extended within the radialgroove 144 may not exit or leave the radial groove 144.

As previously stated, the tip 112 is disposed at the distal end 190 ofthe inner shaft 116. FIG. 5 illustrates a side view of the tip 112removed from the prosthesis delivery system 100 for illustrativepurposes only. The tip 112 includes the generally conical taperedportion 195 disposed at a distal portion thereof, and the tip sleeve 114disposed at a proximal portion thereof. The tip 112 and it componentsmay be constructed of materials such as, but not limited topolyurethane, polyether block amide (PEBA), polyamide polyether blockcopolymer, polyethylene, or other suitable materials.

The tapered portion 195 includes a proximal end 162, a distal end 164,and a lumen 166 extending from the proximal end 162 to the distal end164. The distal end 164 of the tapered portion is also the distal end ofthe tip 112. An outer surface 168 of the tapered portion 195 extendsproximally from the distal end 164 and gradually increases diameter tothe proximal end 162, forming the generally conical shape. The taperedportion 195 further includes a circumferential shoulder 170 at theproximal end 162 extending radially inward from the outer surface 168 toan outer surface 169 of the tip sheath 114.

The tip sleeve 114 is a generally cylindrical tube extending proximallyfrom the proximal end 162 of the tapered portion 195. The tip sleeve 114includes a lumen 172 extending from a proximal end 174 to a distal end176 of the tip sleeve 114. The proximal end 174 of the tip sleeve 114 isthe proximal end of the tip 112. The lumen 172 is sized to receive thespindle 108 (visible in FIG. 2) and a second portion 223 (visible inFIG. 2) of the stent-graft prosthesis 201 (visible in FIG. 2) disposedover the spindle 108. The tip sleeve 114 further includes the pluralityof tabs 152 disposed on a proximal portion 178 of the tip sleeve 114.The tip sleeve 114 is configured to retain the second portion 223 of thestent-graft prosthesis 201 in the radially compressed state for deliveryto a desired treatment location. The tip sleeve 114 is furtherconfigured to release the second portion 223 of the stent-graftprosthesis 201 when the delivery catheter 102 is in the releaseconfiguration.

The plurality of tabs 152 are spaced around a circumference of theproximal portion 178 of the tip sleeve 114, as best shown in FIG. 5. Inthe embodiment of FIG. 5, each tab 152 is formed from the tip sleeve114. Each tab 152 includes a first end 180 coupled to the tip sleeve114, a second end 182 opposite the first end 180, a first side 184 and asecond side 186 opposite the first side 184. The second end 182, thefirst side 184 and the second side 186 are each formed by detaching thesecond end 182, the first side 184 and the second side 186 from the tipsleeve 114. Each tab 152 includes a radially contracted state whereinthe second end 182 is disposed radially inward from the first end 180.Each tab 152 is sized and spaced around the circumference of theproximal portion 178 of the tip sleeve 114 such that the deployment ofthe stent-graft prosthesis 201 and the locking of the spindle 108 to thetip sleeve 114 by the lock mechanism 118 is both insured and optimized.Each tab 152 is configured with a shape memory to return to the radiallycontracted state when not acted upon by an outside force. Mechanicalshape memory may be imparted to each tab 152 by methods known in theart. For example, and not by way of limitation, each tab 152 may beformed of materials that can be made to have shape memorycharacteristics such as, but not limited to nickel alloys (e.g. MP35N),stainless steel, and nickel titanium alloys (e.g. NITINOL). The tabs 152may be formed by a variety of methods, non-limiting examples of whichinclude laser cutting, machining, or other appropriate methods. Whilethe plurality of tabs 152 have been described an integral component ofthe tip sleeve 114, alternatively, each tab 152 may be formed as aseparate component with the first end 180 coupled to the tip sleeve 114by any suitable method. It will be understood that more or fewer tabs152 may be utilized, and that the specific number of tabs 152 shown inFIG. 5. is for exemplary purposes only. Moreover, the shape of theplurality of tabs 152 as shown in FIG. 5 is not meant to be limiting,and other shapes may be utilized.

In the embodiment of FIGS. 1-10, the lock mechanism 118, also referredto herein as a tip travel limiter, includes the plurality of tabs 152 ofthe proximal portion 178 of the tip sleeve 114 of FIG. 5 and the radialgroove 144 of the spindle 108 of FIG. 4. The lock mechanism 118 isconfigured to lock the tip sleeve 114 to the spindle 108 to preventrelative longitudinal movement between the spindle 108 and the tipsleeve 114 when the delivery catheter 102 is in the releaseconfiguration. Stated another way, the lock mechanism 118 is configuredto stop distal movement of the tip 112 (which includes tip sleeve 114)while actively pushing the stent graft out of the tip sleeve 114. Withthe delivery catheter 102 in the delivery configuration, the pluralityof tabs 152 are disposed proximal of the radial groove 144 of thespindle 108, as shown in FIG. 6. As the delivery catheter 102 istransitioning from the delivery configuration to the releaseconfiguration, the tip sleeve 114 and the plurality of tabs 152 disposedthereon move or translate distally. During the distal advancement of thetip sleeve 114, each tab 152 travels over the outer surface 155 of theouter shoulder 154 of the proximal wall 148 of the spindle 108. Morespecifically, each tab 152 is deflected radially outward by the outershoulder 154 as the tab 152 travels distally over the outer surface 155of the outer shoulder 154. Once each tab 152 has traversed the proximalwall 148 and is disposed over the radial groove 144, the shape memoryproperties, described previously herein, of each tab 152 returns eachtab 152 to the radially contracted state, with the second end 182 ofeach tab 152 disposed or engaged within the radial groove 144, as shownin FIG. 7. The inner shoulders 149, 153 of the proximal and distal walls148, 180, respectively, are each of a sufficiently steep angle inrelation to a central longitudinal axis LA_(s) of the spindle 108 thateach tab 152 is prevented from deflecting or moving out of the radialgroove 144 once disposed therein. Thus, with each tab 152 extended intothe radial groove 144, the tip sleeve 114 is locked to the spindle 108and the lock mechanism 118 prevents relative longitudinal movementbetween the spindle 108 and the tip sleeve 114.

With an understanding of the components of the prosthesis deliverysystem 100, it is now possible to describe their interaction to deliverand release the stent-graft prosthesis 201 at a desired treatmentlocation and to limit the longitudinal travel of the tip sleeve 114 ofthe tip 112 relative to the spindle 108.

The stent-graft prosthesis 201 in the radially compressed configurationis loaded onto the delivery catheter 102. More precisely, the firstportion 221 of the stent-graft prosthesis 201 is retained in theradially compressed state by the outer sheath 106 of the deliverycatheter 102, as shown previously in FIG. 2. As best shown in FIG. 9,each opening 217 of the proximal bare stent 209 of the stent-graftprosthesis 201 is disposed over a corresponding spindle pin 120 and thesecond portion 223 of the stent-graft prosthesis 201 is retained in theradially compressed state by the tip sleeve 114. Thus, the stent-graftprosthesis 201 is retained in the radially compressed configuration bythe delivery catheter 102 in the delivery configuration.

Once the prosthesis delivery system 100 is advanced to the desiredtreatment location, the outer sheath 106 is retracted proximally torelease the first portion 221 of the stent-graft prosthesis 201, and thefirst portion 221 of the stent-graft prosthesis 201 returns to theradially expanded state. As described above, the delivery catheter is ina partial release configuration at this stage in the method of use.

Next, the inner shaft 116 (visible in FIG. 2) is advanced distally, andthe tip sleeve 114 travels distally in relation to the spindle 108 torelease the second portion 223 of the stent-graft prosthesis 201, asshown in FIG. 10. The second portion 223 of the stent-graft prosthesis201 returns to the radially expanded state. Thus, the stent-graftprosthesis 201 has fully or completely transitioned from the radiallycompressed configuration to the radially expanded configuration.

The inner shaft 116 is advanced distally until each tab 152 of the tipsleeve 114 travels over the proximal wall 148 of the spindle 108 andeach tab 152 returns to the radially contracted state extending into theradial groove 144, as shown in FIG. 10. Once disposed within the radialgroove 144, the plurality of tabs 152 prevent relative longitudinalmovement between the spindle 108 and the tip sleeve 114. Thus, the lockmechanism 118 locks the spindle 108 to the tip sleeve 114 when thedelivery catheter 102 is in the release configuration.

The delivery catheter 102 is configured such that when in the releaseconfiguration of FIG. 10, there is no longitudinal gap between the tipsleeve 114 and the spindle 108. More precisely, when the tip sleeve 114is advanced distally and the delivery catheter 102 transitions from thedelivery configuration to the release configuration, the proximal end174 of the tip sleeve 114 is disposed proximal of the distal end 142 ofthe spindle 144 such that a proximal portion of the tip sleeve 114overlaps a distal portion of the spindle 108. Stated another way, whenthe delivery catheter 102 is in the release configuration, a portion ofthe tip sleeve 114 is disposed over the radial groove 144 of the spindle108. Thus, there is no longitudinal gap between the tip sleeve 114 andthe spindle 108 that may snag, catch or otherwise damage the stent-graftprosthesis 201 as a distal portion of the delivery catheter 102 isproximally retracted through the deployed stent-graft prosthesis 201.

FIGS. 11-17 illustrate a prosthesis delivery system 1100 having a lockmechanism with a different configuration in accordance with anotherembodiment hereof. As shown in FIG. 11, the prosthesis delivery system1100, includes a delivery catheter 1102 and a stent-graft prosthesis 201of FIG. 3. The delivery catheter 1102 includes a handle 1104, an outersheath 1106, a spindle 1108, a spindle shaft 1110, a tip 1112 includinga tapered portion 1195 and a tip sleeve 1114, an inner shaft 1116, and alock mechanism 1118. The prosthesis delivery system 1100, the deliverycatheter 1102, the handle 1104, the outer sheath 1106, the spindle 1108,the spindle shaft 1110, the tip 1112, the outer sheath 1106, and theinner shaft 1116 are similar to the prosthesis delivery system 100, thedelivery catheter 102, the handle 104, the outer sheath 106, the spindle108, the spindle shaft 110, the tapered tip 112, the tip sleeve 114, andthe inner shaft 116, respectively. Therefore, similar constructiondetails and alternatives will to be repeated. However, with theprosthesis delivery system 1100, the lock mechanism 1118 includes aradial groove 1144 in the spindle 1108, a spring mechanism 1196 disposedin the radial groove 1144, and a plurality of slots 1197 in a proximalportion 1178 of the tip sleeve 1114. The lock mechanism 1118 isconfigured to lock the tip sleeve 1114 to the spindle 1108 to preventrelative longitudinal movement between the spindle and the tip sleevewhen the delivery catheter 1102 is in the release configuration.

As shown in FIG. 12, the spindle 1108 includes the radial groove 1144and the spring mechanism 1196 disposed in the radial groove 1144. Theradial groove 1144 includes a depth D2 optimized to fit/retain thespring mechanism 1196 in either a radially compressed state or aradially expanded state. The spring mechanism 1196 has the radiallycompressed state when the delivery catheter 1102 is in a deliveryconfiguration, and the radially expanded state when the deliverycatheter 1102 is in a release configuration. The spring mechanism 1196is self-expanding to return to the radially expanded state from theradially compressed state. In the embodiment of FIGS. 11-17, the springmechanism 1196 is star-shaped with five (5) points 1198 extendingradially outward, as best shown in FIG. 13. However, in otherembodiments, the spring mechanism 1196 may have alternate polygonalshapes with greater or fewer points 1198 such as, but not limited to atriangular shape with three (3) points, a hexagonal shape with six (6)points, or other shapes suitable for the purposes described herein. Thespring mechanism 1196 may be formed of various materials including, butnot limited to stainless steel, nickel-titanium alloys (e.g. NITINOL),or other suitable materials.

The tip sleeve 1114 of the tip 1112 is a generally cylindrical tubeextending proximally from a proximal end 1162 and adjacent a shoulder1170 of the tapered tip 1112, as shown in FIG. 13. The tip sleeve 1114includes a plurality of slots 1197 spaced around a circumference of theproximal portion 1178 of the tip sleeve 1114. Each slot 1197 isconfigured to receive a corresponding point 1198 of the spring mechanism1196 when the delivery catheter 1102 is in the release configuration, asshown in FIG. 13. Each slot 1197 is a radial opening in the tip sleeve1114 of optimized size and location to enable the corresponding point1198 of the spring mechanism 1196 to be received/engage without radialalignment of the spring mechanism 1196. Stated another way, each slot1197 is sized such that as the tip sleeve 1114 advances distallyrelative to the spindle 1108, the corresponding point 1198 of the springmechanism 1196 will pass through the corresponding slot 1197 without theclinician having to manually align the point 1198 of the springmechanism 1196 with the corresponding slot 1197. The plurality of slots1197 is disposed proximal of the radial groove 1144 of the spindle 1108when the delivery catheter 1102 is in the delivery configuration of FIG.14. The plurality of slots 1197 are disposed over the radial groove 1144when the delivery catheter 1102 is in the release configuration of FIG.15. The plurality of slots 1197 may be formed in the tip sleeve 1114 bymethods such as, but not limited to laser cutting, machining, or othersuitable methods. While shown with five (5) slots 1197, it will beunderstood that more or fewer slots 1197 may be utilized correspondingto the number of points 1198 of the spring mechanism 1196.

In the embodiment of FIGS. 11-15, the lock mechanism 1118 includes theradial groove 1144 of the spindle 1108, the spring mechanism 1196disposed in the radial groove 1144, and the plurality of slots 1197 ofthe proximal portion 1178 of the tip sleeve 1114, as best shown in FIG.15. The lock mechanism 1118 is configured to lock the tip sleeve 1114 tothe spindle 1108 to prevent relative longitudinal movement between thespindle 1108 and the tip sleeve 1114 when the delivery catheter 1102 isin the release configuration.

The interaction of the components of the prosthesis delivery system 1100may now be described with reference to FIGS. 16-17. FIG. 16 shows adistal portion of the delivery catheter 1102 in the deliveryconfiguration, with the stent-graft prosthesis 201 in the radiallycompressed configuration loaded onto the delivery catheter 1102. In thedelivery configuration, an inner surface of the tip sleeve 1114 of thedelivery catheter 1102 pushes radially inward on the plurality of points1198 to radially compress the spring mechanism 1196 to the radiallycompressed state within the radial groove 1144.

Once the prosthesis delivery system 1100 is positioned at the desiredtreatment location, the outer sheath 1106 is retracted proximally torelease a first portion 221 (visible in FIG. 11) of the stent-graftprosthesis 201. The first portion 221 (visible in FIG. 11) of thestent-graft prosthesis 201 returns to the radially expanded state. Next,with a second portion 223 of the stent-graft prosthesis 201 retained ina radially compressed state by the tip sleeve 1114, as shown in FIG. 16,the inner shaft 1116 (visible in FIG. 11) is advanced distally.Advancement of the inner shaft 1116 (visible in FIG. 11) advances thetip sleeve 1114 distally in relation to the spindle 1108. The innershaft 1116 is advanced distally to release the second portion 223 of thestent-graft prosthesis 201, and when released, the second portion 223 ofthe stent-graft prosthesis 201 returns to the radially expanded state.

The tip sleeve 1114 is advanced distally until the plurality of slots1197 is disposed over the radial groove 1144 and the spring mechanism1196 disposed therein is released. When released, the spring mechanism1196 returns to the radially expanded state and each point 1198 of thespring mechanism 1196 extends radially outward and engages or extendsthrough the corresponding slot 1197 of the tip sleeve 1114, as shown inFIG. 17. With each point 1198 engaged or disposed through thecorresponding slot 1197, the spindle 1108 is locked to the tip sleeve1114 by the lock mechanism 1118 and relative movement between thespindle 1108 and the tip sleeve 1114 is prevented.

Thus, when the delivery catheter 1102 is in the release configuration,the proximal portion 1178 of the tip sleeve 1114 is disposed over theradial groove 1144 of the spindle 1108 and there is no longitudinal gapbetween the tip sleeve 1114 and the spindle 1108 that may snag, catch orotherwise damage the stent-graft prosthesis 201 as a distal portion ofthe delivery catheter 1102 is proximally retracted through the deployedstent-graft prosthesis 201.

Although the embodiments of FIGS. 1-10 and FIGS. 11-17 have beendescribed with specific lock mechanisms to limit tip travel and lock adelivery catheter in a release configuration, this is not meant to belimiting, and other lock mechanisms may be utilized. For example, a lockmechanism may include a spring ring disposed within a radial groove in aspindle, and a circumferential groove in an inner surface of a tipsleeve. When the circumferential groove is disposed over the springring, the spring ring may radially expand within the circumferentialgroove to limit tip travel and lock the delivery catheter in the releaseconfiguration.

FIGS. 18-21 are sectional cut-away views of a vessel VE illustrating amethod of delivering and releasing a stent-graft prosthesis 201 of FIG.8 in accordance with an embodiment hereof. With reference to FIG. 18,the stent-graft prosthesis 201 has been loaded onto the deliverycatheter 102 and is shown positioned at a desired treatment location ofan aneurysm AN within the vessel VE. The stent-graft prosthesis 201 isheld in the radially compressed configuration by the delivery catheter102. Intravascular access to the vessel VE may be achieved via apercutaneous entry point for example, in a femoral artery, using forexample, the Seldinger technique, extending through the vasculature tothe desired treatment location. As will be understood, a handle (notshown in FIGS. 18-21), as well as a length of the delivery catheter 102are exposed external of the patient for access and manipulation by aclinician, even as the stent-graft prosthesis 201 is positioned at thedesired treatment location. Although not shown in FIG. 18, optionally, aguidewire and/or a guide catheter may be utilized with the deliverycatheter 102, with the delivery catheter 102 slidably advanced over theguidewire and/or within the guide catheter.

Once the stent-graft prosthesis 201 in the radially compressedconfiguration is positioned at the desired treatment location, the outersheath 106 is manipulated or retracted proximally to release a firstportion 221 of the stent-graft prosthesis 201. When released, the firstportion 221 of the stent-graft prosthesis 201 expands from the radiallycompressed state to the radially expanded state. As the first portion221 of the stent-graft prosthesis 201 expands, the distal bare stent 211of the stent-graft prosthesis 201 engages a wall of the vessel VE distalof the aneurysm AN, as shown in FIG. 19.

In a next method step, the inner shaft 116 of the delivery catheter 102is manipulated or advanced distally to release a second portion 223 ofthe stent-graft prosthesis 201. When released, the second portion 223 ofthe stent-graft prosthesis 201 expands from a radially compressed stateto a radially expanded state and the proximal bare stent 209 of thestent-graft prosthesis 201 engages the wall of the vessel VE proximal ofthe aneurysm AN, as shown in FIG. 20. The inner shaft 116 is advanceddistally until the lock mechanism 118 engages such that the tip sleeve114 of the tip 112 is coupled or locked to the spindle 108 and thedelivery catheter 102 has transitioned to the release configuration.

Following the deployment of the stent-graft prosthesis 201, the deliverycatheter 102 is retracted proximally through the stent-graft prosthesis201 in the radially expanded configuration, as shown in FIG. 21.

While the method of FIGS. 18-21 is described utilizing the prosthesisdelivery system 100, it will be understood that the method may beutilized for other embodiments of the invention including, but notlimited to the prosthesis delivery system 1100.

While various embodiments have been described above, it should beunderstood that they have been presented only as illustrations andexamples of the present invention, and not by way of limitation. It willbe apparent to persons skilled in the relevant art that various changesin form and detail can be made therein without departing from the spiritand scope of the invention. Thus, the breadth and scope of the presentinvention should not be limited by any of the above-described exemplaryembodiments, but should be defined only in accordance with the appendedclaims and their equivalents. It will also be understood that eachfeature of each embodiment discussed herein can be used in combinationwith the features of any other embodiment.

1-26. (canceled)
 27. A prosthesis delivery system comprising: aprosthesis comprising at least one stent and a graft material, whereinthe prosthesis has a radially compressed configuration for deliverythrough a vasculature and a radially expanded configuration fordeployment, a delivery catheter having a delivery configuration and arelease configuration, the delivery catheter including: a tip includinga tapered portion and a tip sleeve extending proximally, wherein the tipsleeve is configured to retain a proximal portion of the prosthesis in aradially compressed state for delivery to a treatment location; aspindle including a plurality of spindle pins; a lock mechanism, whereinthe lock mechanism locks the tip sleeve to the spindle to preventrelative longitudinal movement between the spindle and the tip sleevewhen the delivery catheter is in the release configuration; and an outersheath configured to retain a distal portion of the prosthesis in aradially compressed state for delivery to a treatment location.
 28. Theprosthesis delivery system of claim 11, wherein the delivery catheterincludes the delivery configuration wherein the tip sleeve covers thespindle pins of the spindles, and the release configuration wherein aproximal end of the tip sleeve is distal of the spindle pins, whereinthe lock mechanism locks the prosthesis delivery system in the releaseconfiguration.
 29. The prosthesis delivery system of claim 28, whereineach spindle pin of the plurality of spindle pins includes a smooth,radiused and/or curved profile.
 30. The prosthesis delivery system ofclaim 27, wherein the lock mechanism comprises a radial groove in thespindle distal of the spindle pins and at least one tab on a proximalportion of the tip sleeve, wherein in the delivery configuration the atleast one tab is proximal of the radial groove of the spindle, andwherein in the release configuration the at least one tab extendsradially into the radial groove of the spindle.
 31. The prosthesisdelivery system of claim 30, wherein the at least one tab comprises aplurality of tabs spaced around a circumference of the tip sleeve, andwherein in the release configuration, each of the plurality of tabsextend into the radial groove.
 32. The prosthesis delivery system ofclaim 27, wherein the lock mechanism includes a radial groove in thespindle, a spring mechanism disposed in the radial groove, and at leastone slot in a proximal portion of the tip sleeve, wherein in thedelivery configuration, a distal portion of the tip sleeve is disposedover the radial groove in the spindle and compresses the springmechanism into the radial groove, and wherein in the releaseconfiguration, the at least one slot of the proximal portion of the tipsleeve is disposed over the radial groove in the spindle such that aportion of the spring mechanism extends through the slot to lock thespindle and the tip sleeve together.
 33. The prosthesis delivery systemof claim 32, wherein in the spring mechanism is a star shaped springwith a plurality of points extending radially outwardly, wherein in thedelivery configuration, the distal portion of the tip sleeve pushes theplurality of points radially inwardly to radially compress the springmechanism into the radial groove, and wherein in the releaseconfiguration, the plurality of points extends radially outwardlythrough the slot in the proximal portion of the tip sleeve.
 34. Theprosthesis delivery system of claim 33, wherein the tip sleeve includesa plurality of slots spaced around a circumference of the proximalportion of the tip sleeve, and wherein in the release configuration eachof the plurality of points of the star shaped spring extends through acorresponding one of the plurality of slots.
 35. The prosthesis deliverysystem of claim 28, further comprising: an inner shaft coupled to thetip and extending proximally through the spindle to an actuatingmechanism at a proximal portion of the prosthesis delivery system; and aspindle shaft coupled to the spindle and disposed around the innershaft, wherein the inner shaft is longitudinally slidable relative tothe spindle shaft with the prosthesis delivery system in the deliveryconfiguration.
 36. The prosthesis delivery system of claim 35, whereinwith the prosthesis delivery system in the delivery configuration, theactuating mechanism is configured to push the inner shaft distally withrespect to the spindle shaft such that the tip and the tip sleeve movedistally relative to the spindle until the proximal portion of the tipsleeve is distal of the spindle pins and the lock mechanism locks theprosthesis delivery system in the release configuration.